反应详情

To a solution of CS2CO3 (0.47 g; 1.44 mmol) in 10 ml of methanol was added 0.55 g (2.88 mmol) of 2,6-dichlorobenzoic acid and the resulting mixture was stirred under nitrogen at room temperature for 3 hours. The above mixture was concentrated in vacuo to remove the excess methanol, the residue suspended in 10 ml of DMF and 2-chloromethyl-tetrahydropyrrolo[1,2-b]-1,2,5-thiadiazol-3 (2H)-one 1,1-dioxide (0.5 g; 2.6 mmol) was added. The resulting mixture was allowed to react at 90° C. for 3 hours and then cooled. The mixture was poured into ice/water, extracted with ether/ethyl acetate (3:1; 250 ml), and the organic layer was washed with water and brine, and dried. The organic layer was concentrated in vacuo and the residue was purified by silica gel flash chromatography (35% ethyl acetate in hexane) to afford 0.6 g (61%) of 2-(2,6-dichlorophenylcarbonyloxymethyl) tetrahydropyrrolo[1,2-b]-1,2,5-thiadiazol-3(2H)-one 1,1-dioxide (Formula I: Ar=2,6-Cl2 -phenyl; R1 =H; R2 and R3 together =-(CH2)3 -) as a solid, m.p. 92°-93.5° C.

1. concentrationThe above mixture was concentrated in vacuo
2. customto remove the excess methanol
3. customto react at 90° C. for 3 hours
4. temperaturecooled
5. extractionextracted with ether/ethyl acetate (3:1; 250 ml)
6. washthe organic layer was washed with water and brine
7. customdried
8. concentrationThe organic layer was concentrated in vacuo
9. customthe residue was purified by silica gel flash chromatography (35% ethyl acetate in hexane)